Comparing Interleukin-۶, C-Reactive Protein, Erythrocyte Sedimentation Rate, and White Blood Cell Count for the Early Diagnosis of Acute Pyelonephritis in Children

Background: Urinary tract infection (UTI) is common in children. Differentiating lower UTI from acute pyelonephritis (APN) is of great importance in children since early diagnosis and timely management can prevent kidney scarring and associated complications.Objectives: We aimed to compare the diagnostic performance of serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell (WBC) count with interleukin-۶ (IL-۶) for the diagnosis of APN in children.Methods: This cross-sectional study included ۳۸ children with APN (based on clinical findings and positive urine culture) aged ۱ month to ۱۵ years admitted to Bandar Abbas Pediatric Hospital, Bandar Abbas, Iran, during ۲۰۱۹-۲۰۲۰. Serum CRP, WBC, IL-۶, and WBC count were measured in all children. Age and sex of the participants were also recorded.Results: The mean ± SD age of the children was ۶۵.۸۲ ± ۴۶.۶۷ months, of whom ۲۳ (۶۰.۵%) were girls. The sensitivity of WBC, ESR, CRP, and IL-۶ for the early diagnosis of APN was ۳۹.۵%, ۷۱.۱%, ۶۰.۵%, and ۷۱.۱%, respectively. Taking the results of ESR, CRP, and WBC into account as the basis of diagnosis, altogether ۹.۹۸ pg/mL was the best cut-off of serum IL-۶ for the diagnosis of APN with ۷۰%-۸۰% sensitivity and ۵۶.۵%-۷۳.۷% specificity. A significant correlation was found between serum IL-۶ and CRP, ESR, and WBC with the strongest correlation between IL-۶ and CRP (r = ۰.۴۵۱, P = ۰.۰۰۴). Age and sex did not affect these correlations. The sensitivity of serum IL-۶ at the ۵ pg/mL cut-off for the diagnosis of APN was higher in boys and children younger than ۶ years.Conclusion: IL-۶ can diagnose APN in children aged ۱ month to ۱۵ years with ۷۱.۱% sensitivity. Its sensitivity is superior to CRP and WBC and comparable with ESR in this regard.

کلیدواژه ها:

Acute pyelonephritis ، Interleukin-۶ ، Children ، C-reactive protein ، Erythrocyte sedimentation rate ، Inflammation